From the Department of Surgery (J.B.I., T.D.M., A.T.C., P.R., E.H., LR.T., H.B.C., A.L.E., M.W.C.), The University of Texas Southwestern Medical Center, Dallas, Texas; Division of Burn, Trauma, and Critical Care, Department of Surgery (A.L.E., M.W.C.), The Rees-Jones Trauma Center at Parkland Hospital and the University of Texas Southwestern Medical Center, Dallas, Texas; Department of Pharmacy (J.P.K., C.D.K.), Parkland Hospital, Dallas, Texas; Department of Trauma and Acute Care Surgery (C.T.M.), Baystate Medical Center, Springfield, Massachusetts.
J Trauma Acute Care Surg. 2018 Nov;85(5):867-872. doi: 10.1097/TA.0000000000002024.
Standard low-molecular-weight heparin dosing may be suboptimal for venous thromboembolism prophylaxis. We aimed to identify independent predictors of subprophylactic Xa (subXa) levels in trauma patients treated under a novel early chemoprophylaxis algorithm.
A retrospective analysis of trauma patients from July 2016 to June 2017 who received enoxaparin 40 mg twice daily and had peak Xa levels drawn was performed. Patients were divided into cohorts based on having a subXa (<0.2 IU/mL) or prophylactic (≥0.2 IU/mL) Xa level.
In all, 124 patients were included, of which 38 (31%) had subXa levels, and 17 (14%) had Xa levels greater than 0.4 IU/mL. Of the subXa cohort, 35 (92%) had their dosage increased, and the repeat Xa testing that was done in 32 revealed that only 75% reached prophylactic levels. The median time to the initiation of chemoprophylaxis was 21.9 hours (interquartile range [IQR], 11.45-35.07 hours). Patients who were defined as having lower risk of having a complication as a result of bleeding had a shorter time to starting prophylaxis than those at higher risk (18.39 hours [IQR 5.76-26.51 hours] vs. 29.5 hours [IQR 16.23-63.07 hours], p < 0.01).There was no difference in demographics, weight, body mass index, creatinine, creatinine clearance, injury severity score, type of injury, weight-based dose, time to chemoprophylaxis, or bleeding complications between the cohorts. No independent predictors of subXa level were identified on multivariable logistic regression.
A significant number of trauma patients fail to achieve prophylactic Xa levels. Intrinsic factors may prevent adequate prophylaxis even with earlier administration and higher dosing of low-molecular-weight heparin.
Therapeutic, level IV.
标准低分子肝素剂量可能不适合预防静脉血栓栓塞症。我们旨在确定接受新型早期化学预防算法治疗的创伤患者亚预防 Xa（subXa）水平的独立预测因子。
对 2016 年 7 月至 2017 年 6 月接受依诺肝素 40mg 每日两次并抽取峰值 Xa 水平的创伤患者进行回顾性分析。根据 Xa 水平是否低于 0.2IU/ml（亚预防水平）或高于 0.2IU/ml（预防水平）将患者分为两组。
共纳入 124 例患者，其中 38 例（31%）Xa 水平较低，17 例（14%）Xa 水平大于 0.4IU/ml。亚预防组中，35 例（92%）增加了剂量，对其中 32 例重复进行 Xa 检测，仅 75%达到预防水平。开始化学预防的中位时间为 21.9 小时（四分位间距[IQR]，11.45-35.07 小时）。与高风险患者相比，被定义为因出血而发生并发症风险较低的患者开始预防治疗的时间更短（18.39 小时[IQR 5.76-26.51 小时] vs. 29.5 小时[IQR 16.23-63.07 小时]，p<0.01）。两组在人口统计学特征、体重、体重指数、肌酐、肌酐清除率、损伤严重程度评分、损伤类型、体重剂量、化学预防时间或出血并发症方面无差异。多变量逻辑回归未发现 subXa 水平的独立预测因子。
相当数量的创伤患者无法达到预防 Xa 水平。即使更早给予低分子肝素并增加剂量，内在因素也可能阻止充分预防。
治疗性，IV 级。
